BSL: password: extra check

diff --git a/BSL/BSL_image.cc b/BSL/BSL_image.cc
index 2cc2b10..c131b3e 100644 (file)
--- a/BSL/BSL_image.cc
+++ b/BSL/BSL_image.cc
@@ -37,21 +37,22 @@ bool BSL_image(Logger & log, FTDI & ftdi, bool force_erase)
    log.printf("Image: %s %s\n", header->src, header->time);
 
    //assert(sizeof(IMAGE)/sizeof(data_section_t) == 2); // two sections
-   enum { PASSWORD_LEN = BSL::PASSWORD_LEN };
-   uint8_t password_data[PASSWORD_LEN];
+   enum { PASS_LEN = BSL::PASSWORD_LEN };
+   enum { PASS_ADDR = 0x10000 - PASS_LEN };
+   uint8_t password_data[PASS_LEN];
    const uint8_t * password = 0; // no password -> force erase
    if (!force_erase) {
       if (header->sec_number == 2) {
         // old linker -> two sections: text + vector table
         // select last part of vector table
-        if ((IMAGE[1].address == (0x10000 - 0x20)) && (IMAGE[1].length == 0x20)) {
+        if ((IMAGE[1].address == PASS_ADDR) && (IMAGE[1].length == 0x20)) {
            password = IMAGE[1].data;
         } else
         if ((IMAGE[1].address == (0x10000 - 0x40)) && (IMAGE[1].length == 0x40)) {
-           password = &IMAGE[1].data[0x40 - PASSWORD_LEN];
+           password = &IMAGE[1].data[0x40 - PASS_LEN];
         } else
          if ((IMAGE[1].address == (0x10000 - 0x80)) && (IMAGE[1].length == 0x80)) {
-           password = &IMAGE[1].data[0x80 - PASSWORD_LEN];
+           password = &IMAGE[1].data[0x80 - PASS_LEN];
         } else
            log.printf("no vector table?\n");
       } else {
@@ -59,11 +60,14 @@ bool BSL_image(Logger & log, FTDI & ftdi, bool force_erase)
         memset(password_data, 0xFF, sizeof(password_data));
         for(unsigned i=0; i<header->sec_number; ++i) {
            const struct data_section_t * sec = &header->sec[i];
-           if ( (sec->address < (0x10000 - PASSWORD_LEN)) || 
-                (sec->address > 0x10000) )
+           if (sec->address > (PASS_ADDR + PASS_LEN))
               continue;
-           unsigned offset = sec->address - (0x10000 - PASSWORD_LEN);
-           assert(offset + sec->length <= PASSWORD_LEN);
+           if (sec->address < PASS_ADDR) {
+              assert((sec->address + sec->length) <= PASS_ADDR);
+              continue;
+           }
+           unsigned offset = sec->address - PASS_ADDR;
+           assert(offset + sec->length <= PASS_LEN);
            memcpy(&password_data[offset], sec->data, sec->length);
         }
         password = password_data;